Magnetic printing system

ABSTRACT

A high speed non-impact printing system in which data to be printed is recorded on a magnetic tape as an array of elements to which a magnetic toner is applied and subsequently transferred onto an associated page. The system can be employed to print alphanumeric characters, symbols and the like, as well as pictorial or graphical information, and individual characters or entire lines can be printed during a print cycle.

United States Patent 1191 Ott et al. May 22, 1973 15 1 MAGNETIC PRINTING SYSTEM 3,472,695 10/1969 Ka'ufer ..346/74 MP 3,495,268 2/1970 Hurst ..346/74 MP [75] Invemms' i Brwkfield 3,476,885 11/1969 Shiber 179/100.2E Newwn bmh (30m 3,369,073 2/1968 Scholz 346/74 ES x 73] Assigneez Data Interface Associates, Brook 2,986,608 5/1961 Pett us ...179/l00.2 K field C onn. 2,901,309 8/1959 Atkinson ..346/74 ES [22] Filed: Apr. 30, 1971 Primary ExaminerHoward W. Britton [211 App] No 138 924 Attorney-Weingartem Maxham 8t Schurgin [57] ABSTRACT )ggggfii'; A high speed non-impact printing system in which [58] i g346/74MP 3 ES data to be printed is recorded on a magnetic tape as I o are 178/6 6 an array of elements to which a magnetic toner is ap- 1 plied and subsequently transferred onto an associated page. The system can be employed to print alphanu- [56] References cued meric characters, symbols and the like, as well as pic- UNITED STATES PATENTS torial or graphical information, and individual characters or entlre lmes can be printed during a punt cycle. 3,142,840 7/1964 Smith ..346/74 MP 3,609,238 9/1971 Hodel ..346/74 ES X 30 Claims, 13 Drawing Figures PATENIEDIAYZZIQIS 8,735,416

SHEET 1 BF 6 RT SGNAL FIG. I

INVENTORS OWEN J. OTT FIG 2 DAVID w. GINN BY ha +44 ATTORNEYS PATENTED MY 2 2 I975 SHEET 2 OF 6 INVENTORS OWEN J. OTT

DAVID W. GI N BY N ATTORNEYS PATENTEBHIYZZIBYS SHEET 3 BF 6 BUFFER AMPLIFIER TRACK 7 BUFFER AMPLIFIER 7lb TRACK s BUFFER AMPLIFIER 7lc TRACK 9 FIG. 5A

so 82 84 as KEYBOARD LOGIC CHARACTER PRINTING F GENERATOR MECHANISM Jl V CoMPuTER L88 FIG 6 CHAR/FAX MESSAGE CHARACTERS LINE FEED 22. 2Q FAY J \r-*'\ INvENToRs owEN J. on DAVID w. GINN BY w k mw *M ATTORNEYS P ATENTED 22 5 SHEET 5 [IF 6 may mmwEjmEd mmnEDm wMMETESZ mmnEDm mmmimmsz mwtnm AHOWEIW A'INO CV38 m QM V Aw un 6528 INVENTORS OWEN J. OTT

ATTORNEYS DAVID W. GINN BY NON *MOEME OON mokowkmc wON mmPo m I0 JSUmEw zo l m wE OZEOEQJ A PIIIIENIEI 3,735,416

SHEET 5 OF 6 INPUT OUTPUT To EI CHAR. SHIFT REGISTER CHAR. LoAD BUFFERS BuFFERs O R L 236 J FIRST Z L TAG CONTROL CHAR- SHIFT REGISTER CKT. LAST BUFFER CHAR WRITE/4 wsIgL LoAD FIRST CHARACTER 24o 1 EMPTY SLDT C'RCULATE CoNTRoL FIRST CHARACTER READY NEXT CHARACTER CHARACTER f 242 READY CLOCK TO ALL SHIFT REGISTERS FIG. I0

250 254 TAPE I READER MuLTIPLExER OUTPUT I DATA oPTICAL SCANNER FIG. ll

I T ELE vI SIoN 1/260 64 266 RECEIVER AMPLIFIER DETECTOR TO PRINTER FIG. l2

INvENToRs OWEN LI. OTT DAvID w. GINN ATTORNEYS MAGNETIC PRINTING SYSTEM FIELD OF THE INVENTION This invention relates to high speed printing systems and more particularly to a non-impact printing system utilizing a magnetic image for transfer of indicia onto a writing surface.

BACKGROUND OF THE INVENTION High speed printers are widely employed, for example, in data processing and communication systems to provide a permanent output of information. Most printers in use today are of the electromechanical type in which an inked font on a printing head is caused to im' pact with a confronting sheet in order to transfer the inked character. Electrical signals are employed to selectively energize the fonts to be printed. The automatic typewriter is one very well known form of electromechanical printer in which printing is accomplished one character at a time by appropriate positioning of a type-bearing head in response to an electrical control signal. Such automatic typewriters are capable of operation at speeds of about characters per second. For higher speed operation, typically up to 1,500 characters per second, line printers have been employed wherein an array of type fonts are positioned to define a line of information which is then physically imprinted onto an associated sheet. Such printers require high energy physical impact between the printing head and a sheet to effect imprinting of data. As a result, relatively rugged and substantially constructed apparatus must be employed to accommodate the relatively high energy forces encountered and to maintain precise operation in the presence of such forces. The high energy impact of such electromechanical printers also results in a rather noisy machine, and their mechanical complexity greatly increases their cost.

In an attempt to overcome the disadvantages of electromechanical printers, various techniques have been proposed for avoiding physical impact between a printing head and a receiving sheet. Among such proposed techniques is that of ferromagnetic printing in which a magnetic ink is applied to recorded areas of a magnetic medium, which areas define a character or other image to be printed, and then transferring this image onto an accompanying sheet. Such ferromagnetic printers are shown, for example, in U.S. Pat. Nos. 3,161,544 and 3,254,626.

In the first of these patents (U.S. Pat. No. 3,161,544), a plurality of magnetic recording heads are employed, each having the configuration of a discrete printing character, with apparatus for transferring recorded images of energized ones of these heads onto a paper. The design and construction of heads configured to represent entire characters is extremely critical and seriously limits the utility of such a system. In U.S. Pat. No. 3,254,626 a magnetic printing system is shown in which a segmented printing head is utilized to form characters by means of a matrix of line segments and to transfer a line of recorded characters onto a paper by means of an impacting hammer which is periodically activated by control signals prerecorded at discrete intervals along the recording tape. Neither of these patents show a printing system which is commercially attractive. The requirement of control signals on the magnetic tape can result in misalignment problems between the tape data recording heads and the magnetic head for reading control signals with resulting degradation in system operation and print quality. Moreover, the electromagnetic hammer must operate with considerable energy to effect image transfer and suffers the same disadvantages as outlined above in connection with electromechanical printers. It is an object of this invention to provide a printer of the magnetic type which is constructed and operative to yield a commercially practicable system which is quiet in operation, of relatively low cost, and extremely versatile.

SUMMARY OF THE INVENTION In accordance with the present invention, data is entered onto an endless magnetic tape as a matrix of recorded segments arranged to define a character or other image to be printed. A magnetic ink or toner is applied to the recorded images and is subsequently transferred onto an associated paper or other receiving surface. The printer can be employed to print alphanumeric characters, symbols and the like, and can also be employed to record pictorial or graphical information. Individual characters or symbols can be printed one at a time, or entire lines of data can be imprinted, depending upon the mode of operation desired. The intensity of imprinted marks can be varied by control of the duty cycle, carrier frequency or amplitude of recording drive signals applied to the magnetic recording head, and gray-scale recording can thus be achieved as well as black-white imprinting. Information to be printed can be applied to the printing system from a computer or from a manually operable keyboard, and can also be conveyed to the printing system from a remote source via a telephone line or other communication link.

Briefly, the invention comprises an endless web of magnetic tape which during operation is driven at a uniform rate by a suitable drive motor. Information to be printed is recorded on the tape by means of a recording head and associated encoding electronic circuitry. The magnetized information is moved past a toner station at which magnetizable powder is transferred to the recorded portions of the tape. At a printing station the toner is transferred from the recorded portions of the tape onto a confronting surface by means of a low energy mechanism. At an erase station the magnetized tape portions previously employed for printing are erased and any remaining toner removed from the tape such that the previously magnetized area of the tape is again available for remagnetization with new data to be printed. The magnetic tape can be incremented about its path, transfer of the toner from the tape to an associated surface being accomplished during the dwell interval of intermittent tape motion.

DESCRIPTION OF THE DRAWINGS The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a pictorial view of a magnetic printing mechanism according to the invention;

FIG. 2 is a sectional elevation view illustrating the print transferring mechanism of FIG. 1;

FIG. 3 is an elevation view of an alternative magnetic printing mechanism according to the invention;

FIG. 4 is a partly cutaway pictorial view of a toner applicator and cleaner embodied in the invention;

FIG. 5 is a pictorial view of a multi-track printing head useful in the invention;

FIG. 5A is a schematic representation of cross-talk compensating circuitry useful in the invention;

FIG. 6 is a block diagram broadly illustrative of a printing system in which the invention is useful;

FIG. 7 is a diagrammatic representation of a frame of digital data of a type useful with the invention;

FIG. 8 is a block diagram of a high speed printing system according to the invention;

FIG. 9 is a block diagram of the character generator of FIG. 8 embodied in the invention;

FIG. 10 is a block diagram of a line memory embodied in the character generator of FIG. 9;

FIG. 11 is a block diagram diagram of a system for providing both character and facsimile data for use with the invention; and

FIG. 12 is a block diagram of a technique for receiving data to be printed by use of a television receiver.

DETAILED DESCRIPTION OF THE INVENTION The invention in a typical embodiment is illustrated in FIG. 1. A closed loop of magnetic recording tape 10 is supported by rollers 12 in the path shown. The tape is driven by a capstan and pinch roller 14 in the direction depicted by arrows 16. A recording head 18 is disposed adjacent tape roller 12d and in contact with the magnetizable surface of tape 10. A magnetic erase head 20 is disposed in the position shown between rollers 12a and 12d. The recording and erase heads 18 and 20 are coupled to associated circuitry, to be described, and are respectively operative to record data onto tape 10 and to subsequently erase this data. According to the invention, the data recorded on tape 10 is employed to cause imprinting of indicia onto a writing surface. A toner applicator/cleaner 22 is disposed in juxtaposition with tape 10 with an aperture 24 thereof confronting the magnetizable surface of tape 10 at a position adjacent recording head 18. Applicator/cleaner 22 is operative to apply a magnetic toner powder to the recorded areas on tape 10 provided by head 18, and is also operative to remove toner from tape 10 after erasure by head 20 of the data recorded thereon.

A sheet of paper 26 or other suitable material onto which data is to be printed is generally supplied from a reel (not shown) and fed through the printing system in the manner illustrated in FIG. 1. The sheet of paper is moved in the direction indicated by arrows 17 and through pinch rollers 38 and 40 and then along the width and in confronting relation to the magnetizable surface of tape 10. The paper is then fed around roller 36 and thence to pinch rollers and 32, over roller 28 and to a receiving position which may include means for removal of sections of the sheet 26. As seen more clearly in FIG. 2, a platen 42 is disposed on the side of tape 10 opposite to the magnetizable surface thereof and in contact or near contact therewith. The paper 26 confronts the recorded surface of tape 10 and the opposite surface of paper 26 is confronted by a wiping plate 44. Plate 44, which typically is formed of a plastic sheet material, is cantilevered in position between paper 26 and a transfer cam 46. Transfer cam 46 is disposed along the length of tape 10 at the position at which printing is to be accomplished, this cam being rotated to sequentially transfer data recorded on tape 10 onto the confronting portions of sheet 26.

The transfer cam 46 includes an elongated cylinder at least equal to and preferably longer than the active length of tape 10 from which printing is accomplished.

A raised helical ridge 48 is formed on the surface of the cylinder, the cam being positioned with respect to tape 10 such that the helical ridge 48 urges paper 26 into contact with the confronting surface of tape 10 via the interposed wiping plate 44. Upon rotation of cam 46, the helical ridge 48 is operative to traverse the active length of tape 10 to sequentially cause transfer of toner adhered to the recorded areas of tape 10 onto confronting areas of sheet 26 to effect imprinting of data.

The helical ridge 48 is of a pitch to provide sequential transfer of a line of data onto sheet 26 during a predetermined angular rotation of transfer cam 46. In the illustrated embodiment, the helical ridge 48 is arranged over about one third of the circumferential surface of cam 46 to provide imprinting by rotation of cam 46 through an angle of about The wiping plate 44 is effective to decouple the tangential forces of helical ridge 48 occasioned by the motion of ridge 48 relative to sheet 26, and also provides a small wiping action on the surface of sheet 26 for improved image transfer. A contact 47 is connected to the shaft of transfer cam 46 and is rotatable therewith and disposed to make electrical contact with an associated stationary contact 49 once per revolution. This switch closure provides a line start signal for use in printing lines of data, as will be described.

The toner is usually composed of resin coated magnetic particles which must be heated in order to fuse or set the toner permanently on the page. Fusing of the toner is accomplished by an elongated rod heater 37 disposed adjacent roller 36 over which sheet 26 passes, with an arcuate reflector 39 disposed around heater 37 to concentrate heat onto the confronting portion of sheet 26. The actual fusing temperature is a function of the particular toner employed; typically, fusing can be accomplished at a temperature of about 250 F, and it is only necessary to heat the page for a fraction of a second to set the image. Sheet 26 traverses heater 37 for a time sufficient to fix the toner thereon. Toner fixing can also be accomplished by use of a transparent heated glass disposed across sheet 26 at a position adjacent the printing station. Such a glass heater is useful to permit reading of printed data on sheet 26 while it is being set.

Tape 10 is driven around its closed path with intermittent motion, transfer of data from the tape onto sheet 26 being accomplished during the period of dwell. The sheet 26 can be intermittently moved after imprinting of a line of data or, alternatively, can be continuously moved with momentary stoppage of the sheet for printing being provided by braking action of the transfer cam 46. In order to minimize the level of mechanical energy employed in the system, an appreciable portion of the print cycle can be employed to transfer the image from the tape to the page. Instantaneous forces are thereby maintained at a relatively low level, which also results in a system that is extremely quiet.

The platen 42 is surfaced or constructed of an elastomeric material which deforms under pressure of the helical ridge 48 of transfer cam 46. This resilient surface compensates for the curving motion of the transfer cam which could otherwise generate non-uniform forces maximized at a point tangent to the motion of the ridge 48. The resilient platen also serves to compensate for small differences in alignment between the tape 10, sheet 26, wiping plate 44 and transfer cam 46. Alternatively, the helical ridge 48 can be formed of a resilient material and employed with a rigid platen 42 for providing transfer of toner from tape onto sheet In some instances it may be desirable to employ both a resilient platen and a resilient helical ridge. Various well known materials are suitable to provide the intended resiliency and low friction to avoid impeding tape motion, Neoprene with a Teflon coating being one such material. The major drive elements of the tape and paper transport apparatus can be in continuous motion with the intermittent motion being confined to the tape loop and paper feed roller. Little energy is expended accelerating and decelerating mechanical components, thereby minimizing the mechanical energy levels, as well as the cost and noise of the system. In some instances it may be desirable to decelerate the tape at a controlled rate to avoid disturbance of the toner applied thereto in the event that forces caused by intermittent tape motion tend to disturb the toner.

An alternative embodiment of the electromechanical portion of the printer is illustrated in FIG. 3. The tape 10a in this embodiment is supported by rollers 12e in a generally rectangular loop with the magnetizable surface inwardly of the loop. A platen 42a is arranged along one side of the tape loop confronting the non-magnetizable surface thereof. A sheet 26a of paper or other suitable sheet material confronts the magnetizable surface of the tape opposite platen 42a, and wiping plate 44a is disposed adjacent the other surface of sheet 26a. The transfer cam 46a confronts wiping plate 44a and is operative upon rotation thereof to sequentially cause depression of sheet 26a into engagement with confronting portions of tape 10a by action of the helical ridge 48a, as described. A toner fixer (not shown) is also employed as in FIG. 1.

A recording head 18a is disposed adjacent themagnetizable surface of the tape in the position illustrated, with a toner applicator 50 disposed adjacent platen 42a to apply toner to the recorded areas of tape 10a as recorded by head 18a. An erase head a is disposed adjacent the tape as illustrated with a toner cleaner 52 disposed opposite the erase head and confronting the magnetizable tape surface for purposes of removing toner therefrom upon erasure of recorded data from the tape.

In the embodiment of FIG. 1, the toner applicator/- cleaner 22 is operative to apply toner to the tape as well as remove toner therefrom. In the present embodiment, however, separate devices are employed for application of toner to the recorded tape areas and for removal of toner from the erased tape areas. The tape 10a is driven with intermittent motion about its path by means of a pinch roller 54 and capstan 56.

The capstan is of circular shape except for a flat portion 58 which, upon rotation of the capstan, clockwise in FIG. 3, provides a dwell during which the image of data on the tape 10a is transferred to sheet 26a. The magnetizable surface in this embodiment is inside of the tape loop with the transfer cam 46a being disposed within the loop adjacent the active tape surface. In the embodiment of FIG. 1 the active surface is outside of the loop as is the associated transfer cam 46. It will be appreciated that the various elements of the tape transport can be 'disposed at various positions with respect to the tape loop depending upon the physical configu: ration of a particular embodiment. In this embodiment the switch for providing a line start signal is provided on capstan 56. A contact 57 is attached to the capstan and is movable therewith to engage stationary contact 59. In order to suit specific physical configurations, magnetic recording of data onto tape 10 can also be accomplished through the non-oxide coated side of the tape.

The toner applicator 22 is illustrated in FIG. 4 and includes a closed cylindrical housing 60 having an aperture 62 which confronts the magnetizable surface of tape 10. A cylindrical brush including bristles 62 extending from a hub 64 is concentrically mounted within housing 60 and is rotatable therein with the ends of bristles 62 being in contact or slightly separated from the inner surface of housing 60. A supply of magnetic toner powder is contained within housing 60 and is dusted onto the recorded areas of tape 10 by action of the bristles 62. A ridge 64 is provided on the inner surface of housing 60 across the width thereof and is operative to dislodge any clumps of toner which may accumulate on the bristle ends. A second aperture 66 can be provided in housing 60 confronting a portion of tape 10 near the erase head for removing toner from the erased portions of the tape. Rather than employing a single toner applicator/cleaner, separate devices can be employed for respective purposes, such as shown in FIG. 3. The toner cleaner can also be combined with a tape demagnetizer to accomplish both erasure of data and removal of toner by a single instrumentality.

Data is recorded on the tape for forming characters and other information to be printed, by means of an array of line segments or other elements arranged to form intended indicia. A typical magnetic head for providing such arrays of line segments is shown in FIG. 5 in which 12 head segments 70 are provided in staggered relationship as illustrated. Six even-numbered segments and six odd-numbered segments are provided, each having a respective coil winding 72. The operative edge 73 of each head segment 70 confronts a magnetic barrier 74 disposed between the even and odd-numbered segments. The head is arranged with barrier 74 extending across the width of the magnetic tape such that the head gaps define a plurality of line segments across the width of the tape. Each line segment to be printed is recorded as a carrier burst to compensate for the dependence of the magnetic toner on field gradients. By use of a carrier burst rather than a DC pulse, areas to be printed can be fully covered with toner.

The staggered head segments are electronically compensated by proper arrangement of character data applied to the heads to permit printing of an array of line segments which are in alignment across the tape. In essence, those line segments which are mechanically delayed by reason of the construction of the head are electronically advanced to bring these segments into alignment with the non-delayed line segments.

Characters and other symbols being printed by the illustrated embodiment are defined by a matrix of line segments, the matrix being composed of twelve vertical elements within each column and columns. Each character is printed one column at a time by selective energization of the head segments 70 of the magnetic head. The formation of characters by an array of elements is per se well known and need not be described in detail herein.

The intensity of the pattern recorded on tape can be varied to achieve gray-scale recording. Such variation can be accomplished by varying the drive level of the signals applied to the magnetic head, by varying the carrier frequency employed, or by adjustment of the duty cycle of the carrier signal, as well as any combination of such techniques. The variable intensity recorded pattern permits the adherence of corresponding variable amounts of toner thereon. The toner when transferred to page 26 is of varying intensity and results in a gray scale of representation of particular interest in utilizing the invention for facsimile or graphical data display.

As is known, multi-track magnetic recording heads experience cross-talk between head segments which can detract from the quality of data recorded by respective head segments. In a well designed head, crosstalk can often be maintained at an acceptably small level. In some instances, however, it may be desirable to employ a less expensive recording head which itself has a rather high cross-talk characteristic, and to compensate for such cross-talk by means of associated circuitry. Even where a particular multi-track head has a low cross-talk level, it may be desirable to further reduce cross-talk by use of such compensating circuitry. One such compensation technique is depicted in FIG. A wherein there is shown, by way of example, three buffer amplifiers 71a, b and c, each having a differential output. These amplifiers are associated with adjacent tracks of the recording head, say, tracks 7, 8 and 9 respectively. The positive output of each amplifier is coupled to a respective coil 72 of the associated head segment. The positive output of each amplifier is also coupled via a respective adjustable impedance element 73 to the negative output of each adjacent amplifier, while the negative output of each amplifier is also coupled via an adjustable impedance element 75 to the positive output of adjacent amplifiers. Each buffer amplifier 71 is thus cross connected to the adjacent buffer amplifiers in phase opposition to null the effects of cross-talk induced in each head winding 72. The impedance elements 73 and 75 are initially adjusted to achieve the desired nulling effect. Other compensating techniques can of course also be employed in the invention, many of these techniques being well known in the digital recording art, such as alteration of the carrier drive polarity or frequency from track to track to minimize crosstalk effects.

Before considering the detailed operation of the novel printer, it will be helpful to discuss the overall system in which the printer is employed. The novel high speed printer is especially useful as an output device for a manually operable keyboard or for a computer. Referring to FIG. 6, there is shown a keyboard 80 coupled to logic circuitry 82 which drives a character generator 84 operative to provide signals to printing mechanism 86 to effect the printing of data. The keyboard 80 provides a coded output signal representing the actuated key, while logic 82 conditions the received signals into a format suitable for driving character generator 84. Data can also be provided to character generator 84 by means of a computer 88 which can be suitably programmed to provide data to character generator 84 of the requisite format. Alternatively, the computer can provide signals representing characters or other data to be printed to logic 82 for formatting and application to the character generator 84.

The printing system is operative to receive character data in a suitable code such as an ASCII code and facsimile data in a different code, and both characters and facsimile can be produced on a page in response to received information. A typical frame of data received by the printer is illustrated in FIG. 7 and includes a code word 90 which identifies whether ASCII or facsimile information is being received. A series of message characters 92 are then provided in the data frame, the frame ending with a code 94 which is a line feed command to cause the printer to shift this paper to a subsequent line.

It is a major feature of the invention that the printing system is operative to produce both character and facsimile data with common apparatus and circuitry, asillustrated in FIG. 8. The system is coupled to a source of data which may be, for example, a computer located at the site of the printing system or remote therefrom and connected via a suitable communication link such as a telephone line. The illustrated embodiment is especially adapted for use as a data terminal for conveying data to and from a remote central computer. Data received in serial form on a transmission link is applied to a receive modem which is operative to convert modulated pulses received into DC. pulses for application to serial/parallel converter 102. Parallel data from converter 102 is applied to the input of line memory 104 operative to assemble lines of data to be printed. The line memory 104 can also receive local parallel data from a manually operable keyboard 106, this data from keyboard 106 also being applied to a parallel/- serial converter 108. The serial output of converter 108 is applied to a transmit modem 110 which is operative to apply modulated pulses to a transmission link for transmission to the remote computer.

Since the printer is capable of printing information at a rate greater than normally employed data transmission rates, and is asynchronous with the input data by means of the line memory, a measure of the proportion of memory which is full can be used to control power to the printer drive motor in order to reduce system wear when the printer is used in a system having a low data rate. Data from line memory 104 is applied to a motor control circuit 117 which provides drive signals to the printer motor. The drive motor can be energized after a whole line of characters resides in memory 104, and de-energized thereafter. As a result, motor operation is at a low duty cycle, typically one tenth of the time to convey a line of data for printing.

The system is completely interactive with a remote processor. Remote data can be stored in line memory 104 for sub-sequent printing, as can local data from keyboard 106. Locally generated data can also be directed to the remote processor. The parallel output of line memory 104 is applied to a path switch 112 and also to a character/facsimile detector 114 and a line feed detector 116. Detector 114 is operative to determine whether received data represents character information or facsimile information, as determined by the nature of the data word 90 which is part of the data frame depicted in FIG. 7. The detector 116 is operative to detect the presence of the line feed code 94 of the data frame for purposes of advancing the paper in the printing mechanism to a succeeding line position. A different line feed code 94 is employed with each code 90 corresponding to whether character data or facsimile data is present in the message frame.

In response to respective line feed codes, detector 116 provides two control signals, respectively labeled character feed" and facsimile feed, which are effective to advance the paper by a respective amount. It is generally desirable to employ a smaller line spacing for purposes of facsimile printing in order to enhance the resolution of printed data. Typically, a line spacing of 0.01 inch is employed for facsimile reproduction, while for character reproduction a line spacing of 0.2 inch is typically employed. In accordance with a command signal (charfax) applied by detector 114 to path switch 112, parallel data from memory 104 is directed either to parallel/serial converter 118 or to character generator 120, depending upon whether received data represents characters or facsimile information, respectively. Character information is applied in parallel form to the head segments of the recording head for printing of the respective characters, in a manner to be more fully described hereinafter. Facsimile information, on the other hand, is applied in serial form by converter 118 to a single recording head, .which may be a head separate from the character recording head or preferably one head segment of the character recording head.

For printing data from keyboard 106, it is often useful to provide a means for visual inspection of a line of print, for example to determine whether any printing errors exist. In order to view a line of printed data,the paper can be advanced by a predetermined amount, say by one line, by means of paper feed control 107 energized upon actuation of a suitable control on keyboard 106, and then when again ready to print the paper is automatically retracted by means of the keyboard control and feed control 107 to the original line position.

The character generator 120 is illustrated in FIG. 9 and is operative in response to received data to suitably energize the individual tracks of the multi-track recording head for formation of the characters or other data on the magnetic tape for use in printing onto an associated sheet. Data to be printed is received from a line memory 200 and is applied as a parallel word to a load control gate 202 and thence to a storage buffer 204. The parallel data from memory 200 is also applied to a special character detector 206 which is operative to de-energize a latching circuit 208. The latching circuit is energized by a line start signal received from the printing mechanism to indicate the commencement of a particular line to be printed, and, in turn, causes actuation via an AND gate 222 of a latching gate 214. The parallel output data from storage buffer 204 is coupled to the data input of a read-only memory 210.

The read-only memory 210 contains data for representing characters and other indicia to be printed in the form of multiple columns of segmented marks. The character to be printed is specified by the data in storage buffer 204.

The control inputs of the read-only memory 210 are coupled to a digital counter which includes a column clock 212, latching gate 214 and a chain of dividers 216 connected as shown. The clock 212 runs at a predetermined rate, the four output signals provided by the respective dividers 216 produce a four bit digital word which represents the number of the column of the particular character to be printed. The clock signal is also applied -to a modulation input of the read-only memory 210 and in effect provides a carrier signal such that the output signals of the memory to the buffer amplifiers 218 are in the form of carrier bursts. The magnetic toner is responsive to flux gradient so that the carrier signal allows the toner to be applied to the entire recorded areas of the magnetic tape rather than at the edges of the recorded areas as would occur if DC pulses were employed.

The storage buffer 204 identifies a character to be printed, while the respective columns of this character are specified by the control input to the read-only memory 210, provided by dividers 216, the column data being printed by selective energization of the buffer amplifiers 218 and associated magnetic head segments by memory 210. Upon readout of all of the columns of a particular character, an end of character bit (EOC) is supplied by the memory 210 via an AND gate 220 to load control gate 202 and to latching gate 214 to provide an indication that a character has been completed. Such end of character indication is useful for example to produce variable width characters. Since an indication is provided of the ending of a particular character, the next character can be commenced any time after the receipt of this end of character signal. A special character signal received by detector 206 causes inhibiting of further printing until the next line start signal is received. The character ready" signal is provided by the line memory 200 and is employed to energize AND gate 222 to activate latching gate 214.

As discussed, facsimile information is printed as a series of elements selectively provided along successive lines of the page to represent received information. In the present embodiment, facsimile data is printed by selective energization of one of the magnetic head segments of the multi-track head. Referring again to FIG. 9, facsimile data from memory 210 is applied via an OR gate 224 to the associated buffer amplifier 218 for application to the corresponding head segment.

The line memory 200 is operative to store a plurality of characters which are sequentially applied to the character generator for consequent recording and printing. A preferred memory configuration for this purpose is depicted in FIG. 10 and includes an array of input character buffers 230 coupled to a plurality of shift registers 232 which, in turn, are coupled to an array of output character buffers 234. Each of the shift registers 232 has associated therewith an input character buffer and an output character buffer which effectively serve as the first and last stages of the shift register. Each register is operative to recirculate data therearound, the bit at the last shift register stage being shifted back into the first register stage for recycling through the register. Data words are applied in parallel to the input character buffers 230 and are shifted in parallel along the shift registers 232 to the output character buffers 234 where the parallel word can be applied to load control gate 202 of the character generator (FIG. 9).

In the present embodiment a seven bit data word is employed to represent a character and thus seven shift registers and associated input and output character buffers are employed. The length of the shift registers is determined by the desired storage capacity of the line memory and in the present embodiment 128 stage registers are employed. A tag shift register 236 of identical length as the shift registers 232 is provided and has as an input stage thereof an input tag buffer 238. The tag shift register 236 has its output coupled to a control circuit 240 which provides control signals representative of the first character and last character stored in the memory. Memory operation is governed by control circuitry 242 driven by a clock 244, the clock also providing timing signals to all memory shift registers.

Upon receipt of a data word applied to input character buffers 230, and a character ready signal from the source of data applied to control 242, the received data word is loaded into the input character buffer. The tag shift register 236 and tag buffer 238 comprise a tag track which initially contains all zeros. Upon receipt of a character, a tag bit, which is a logical one," is written into the input tag buffer 238 by operation of control circuitry 242. As will be described, this tag bit circulating along the tag track is employed to denote that data is in a particular memory location and to control loading and unloading of this data from memory.

Data is assembled in the shift registers 232 as a succession of characters which represent a block of data. The data block can include a plurality of characters to be printed, together with line shift commands operative to advance the printing mechanism to succeeding line positions. The tag track contains a tag bit, which is a logical one in the present implementation, in each tag register position associated with the corresponding position of shift registers 232 containing valid data. There is no tag bit, that is a logical zero," present in those register positions of tag register 236 corresponding to the positions of registers 232 containing invalid data.

The beginning and end of a data block is readily ascertained by virtue of the unique line memory by sensing an upward transition of the tag track, from a zero to a one state, indicating the start of a data block. Data can be entered into memory immediately following the register position containing the last character of the previous data block. The data block is sequentially moved through shift registers 232 and the first character in the block may be transferred to the output character buffers 234, if buffers 234 are in condition to accept such data; or the data block is recirculated back into shift registers 232 around which the data block is sequenced until the system permits transfer of this data to the recording head of the printing mechanism.

Under the government of the clock 244, the first character loaded into the input character buffers 230 will shift through each stage of shift registers 232 until this character reaches the last stage thereof. The tag bit in the last stage of the tag register 236 will be sensed by control circuit 240 in conjunction with a next character" signal where the transition to a one stage will cause loading of the data from the last stage of shift registers 232 to the output character buffers 234.

When the first tag bit is present in control circuit 240, and a .next character signal is present, a signal labeled first character ready is applied to control 242 which provides a load first character" command to output character buffers 234 to permit shifting of the character from shift registers 232 into the output character buffers. The absence of a next character signal in control circuit 240 indicates that the output character buffers 234 contain data, and thus any data at the last stage of shift registers 232 will be recirculated to the first stage of the shift registers rather than being shifted into the output character buffers. Shifting of data into the output character buffers for application to the character generator is accomplished via the next character signal from the read-only memory 210 which is part of the character generator.

Upon receipt of the next character signal by control 242, the character which is in shift registers 232 at a location determined by the presence of the first tag bit occurring after zero bits is loaded from the output of shift registers 232 into the output character buffers 234. As data is loaded into the output character buffers, a zero is written into the tag track by control circuit 240 to designate the next character as first character. A character thus resides in the output character buffer for use when needed by the character generator. A subsequent next character is similarly loaded into the output character buffer for use by the character generator.

The tag track provides a ready means of indicating that data is in memory and is available for application to the character generator. When the tag track undergoes a transition to a one state, the data associated with that tag bit is the first character in the data block which is available at the output of the shift register for transfer to the output character buffers and thence to the character generator. When the last character in a data block reaches the output of the shift register, the tag track will fall to a zero" condition which indicates that a vacant memory position is available immediately following the existing block of data.

Upon initial operation of the memory, no data is present and no data is present in the tag track. Logic control 242 includes an all zeros detector to denote an all zero condition during which data can initially be accepted at any time.

It will be appreciated that the high speed printing system provided by the invention is effective to print both character and facsimile data, and both types of information can be imprinted selectively on a single page. A tape producing typewriter can be employed to provide a coded tape containing character data, which can be employed in conjunction with pictorial or graphic information as a means for obtaining both character and facsimile information for transmission to the printing system. Referring to FIG. 11, there is shown a tape reader 250 and an optical scanner 252, each of which has its output coupled to a multiplexer 254.

The tape reader 250, which typically can be of either the magnetic or optical variety, is operative to read the character information encoded on tape and to provide coded signals representing character data to multiplexer 254 for transmission to the printing system. The optical scanner 252 operates at times indicated by control signals from tape reader 250 to scan pictorial or graphical information and to provide facsimile data to multiplexer 254 for transmission to the printing system. In this manner, a stream of data containing both character and facsimile information can be applied to the printing system and which can be employed by the invention to print both types of data. Requisite codes indicating the type of data being transmitted as well as line start and other control codes can be assembled by multiplexer 254 into the output data stream.

The simplicity and efficiency of the novel printing system permits its use as a data output terminal by a wide class of users, including its use in homes for printing out information received, for example by subscription, such as stock quotations and news. As described above, data originating from a source remote from the printing system can be transmitted thereto by any suitable transmission link. A transmission path which is especially suitable for home use makes use of the ubiquitous television receiver. As depicted in FIG. 12, a television receiver 260 and more particularly its video amplifier 262 can be employed as a low power transmitter, and information to be printed can be multiplexed on a subcarrier which will radiate from the video amplifier 262 without degradation of the normal television video and sound information. Other video receivers, such as cathode ray tube terminals, can also be used as a source of radiated data for receipt by the novel printing system.

The radiated subcarrier can be readily detected by an antenna 265 and associated subcarrier detector 266 to provide demodulated data for operation of the printer. This technique eliminates any requirement for use of common carrier or dedicated lines, as well as any need for associated modern equipment. The printer and associated subcarrier detection apparatus can be embodied in a small cabinet for practical use in a home or office and at a price well within the reach by the public at large.

Various modifications and alternative implementations of the invention will occur to those versed in the art without departing from the true scope of the invention. Accordingly, it is not intended to limit the invention by what has been particularly shown and described except as indicated in the appended claims.

What is claimed is:

l. A magnetic printing system comprising:

a magnetic recording tape;

tape transport means adapted to move said recording tape in a predetermined path;

magnetic recording means disposed in operative association with said tape for recoding data thereon representing information to be printed;

means disposed in operative association with said recording tape for erasing datarecorded thereon;

toner means disposed in relation to said tape and operative to apply a magnetic toner to recorded areas on said tape;

a data receiving sheet having a portion thereof disposed in planar confronting relation with a portion of said recording tape;

sheet transporting means for moving said data receiving sheet in a predetermined path;

platen means disposed adjacent a surface of said portion of said tape;

transfer means disposed on the opposite surface of said portion of said tape as said platen means and continuously moveable in a repetitive cycle and operative during a portion of each cycle to urge the confronting portions of said tape and said sheet into engagement in a sequential sweep along the length thereof, thereby to transfer said toner on the recorded portions of said tape onto the confronting surface of said sheet; and

means for fixing the toner applied to said sheet.

2. A magnetic printing system according to claim 1 wherein said platen means is formed of a resilient material.

3. A magnetic printing system according to claim 1 wherein said transfer means includes a resilient member for urging said tape and said sheet into engagement.

4. A magnetic printing system according to claim 1 wherein said toner means includes means containing a supply of toner;

means for applying said toner to said recorded areas of said tape; and

means for removing toner from erased areas of said tape while containing said toner substantially within said containing means.

5. A magnetic printing system comprising:

an endless web of magnetic recording tape supported for movement in a closed path;

tape transport means for moving said endless web of tape with intermittent motion about said closed path;

magnetic recording means including a recording head in operative relation to a surface of said tape for recording data thereon representing information to be printed;

a web of sheet material supported for intermittent motion about a predetermined path, said sheet material having a portion disposed in confronting rela tionship with a portion of said tape having data recorded thereon;

sheet transport means for moving said sheet material along said predetermined path;

means for applying a magnetic toner to a surface of said tape on areas having recorded data thereon and in a pattern corresponding to the pattern of recorded data;

means continuously moveable in a repetitive cycle and operative during a portion of each cycle when said endless web of tape and said sheet material are at rest to urge the surface of said tape containing said toner into engagement with the confronting surface of said sheet material sequentially along a length of said sheet material, thereby to sequentially transfer said toner onto said sheet material in a pattern defined by said recorded areas;

means for fixing said toner applied to said sheet material; and

means for erasing said data recorded on said tape after transfer of said toner onto said sheet material.

6. A magnetic printing system according to claim 5 wherein said transfer means includes:

a platen disposed adjacent one surface of said tape;

an elongated generally cylindrical transfer cam supported for rotation about its longitudinal axis and disposed with said longitudinal axis along the length of said tape and adjacent the opposite surface of said tape to said platen, said transfer cam including a ridge helically disposed around a predetermined portion of the cylindrical surface thereof and operative to urge the confronting portions of said tape into engagement with the confronting surface of said sheet material to cause sequential transfer of toner from said recorded areas onto said sheet material; and g a wiping sheet interposed between said transfer cam and said sheet and operative to minimize spurious forces during wiping of said tape and said sheet into engagement.

7. A magnetic printing system according to claim 5 wherein said recording means includes a line memory for storing a line of data to be printed;

a character generator operative in response to parallel data from said line memory for energization of said multi-track head for recording of data to be printed on said tape;

a recording head for recording facsimile data in the form of a sequence of like marks;

means for conveying facsimile data to be printed from said line memory to said facsimile head;

means for detecting whether data in said line memory is character data or facsimile data and operative to cause transfer of data to said multi-track head or said facsimile head, respectively; and

means operative in response to data in said line memory for detecting a line feed signal and to provide control signals to said sheet transport means to govern line spacing of said sheet material.

8. A magnetic printing system according to claim wherein said tape transport means includes a capstan disposed in driving relationship to said web of magnetic recording tape and adapted for rotation about its axis;

said capstan being of cylindrical peripheral configuration for driving said web, except for a peripheral portion disposed away from said web for providing a dwell period for said web during each revolution of said capstan.

9. A magnetic printing system according to claim 5 wherein said toner means includes a housing having a brush disposed therein and adapted for rotation about its axis;

a supply of toner in said housing;

an aperture provided in a wall of said housing and disposed adjacent the surface of said tape to which toner is to be applied;

said brush upon rotation within said housing being operative to apply toner through said aperture onto said recorded areas of said tape.

10. A magnetic printing system according to claim 5 wherein said toner means includes means for removing toner from the surface of said tape after data recorded on said tape has been erased.

11. A magnetic printing system according to claim wherein said toner means includes a cylindrical housing having a cylindrical brush coaxially disposed therein and adapted for rotation about the common axis;

a supply of toner in said housing;

a first aperture provided in the cylindrical wall of said housing and disposed adjacent the surface of said tape to which toner is to be applied;

a second aperture disposed in the cylindrical wall of said housing and disposed adjacent the surface of said tape at a position at which toner is to be removed;

said brush upon rotation within said housing being operative to apply toner through said first aperture onto said recorded areas of said tape and to remove through said second aperture toner from the erased areas of said tape, said toner supply remaining substantially within said housing.

12. A magnetic printing system according to claim 5 wherein said magnetic recording means includes a multi-track recording head for providing a plurality of like data marks on said tape;

character forming logic for selectively energizing said multi-track head, said logic including means for storing a character to be printed;

counter means for providing digital representations identifying the column of a particular character to be printed; and

a read-only memory operative in response to said column identification and said stored character to provide output signals to said multi-track recording head for selective energization thereof.

13. A magnetic printing system according to claim 12 wherein said signal is applied to said recording head in the form of carrier bursts such that toner is applied to entire recorded areas of said tape. 5 14. A magnetic printing system according to claim 5 wherein said transfer means includes: an elongated generally cylindrical transfer cam supported for rotation about its longitudinal axis and including a ridge helically disposed around a prede- 10 tennined portion of the cylindrical surface thereof and operative ,to urge the portion of said tape having data recorded thereon into engagement with the confronting surface of said sheet material to 15 cause sequential transfer of toner from said recorded areas onto said sheet material.

15. A magnetic printing system according to claim 14 wherein said transfer means includes a platen disposed adjacent said tape on a side opposite to said transfer cam.

16. A magnetic printing system according to claim 14 wherein said ridge is of a resilient material.

17. A magnetic printing system according to claim 5 wherein said recording head is a multi-track head for providing a plurality of like data marks on said tape, and said recording means includes character forming logic for selectively energizing said multitrack head for applying data onto said tape representing information to be printed.

18. A magnetic printing system according to claim 17 wherein said recording means further includes memory means for storing one or more lines of data to be printed.

19. A magnetic printing system according to claim 17 wherein said magnetic recording means includes means for providing crosstalk compensation between adjacent tracks of said multi-track head.

20. In a printing system whichincludes means for printing information in the form of selected combinations of like indicia and means for imprinting said indicia on a sheet, logic circuitry for providing said selected combinations of indicia and comprising:

a memory for storing data representing first and second forms of information to be printed;

means for recognizing each of said forms of information and for providing respective control signals in response thereto;

means operative in response to one of said control signals to convey data representing said first form of information from said memory to said imprinting means for printing said first form of information as first selected combinations of said like indicia; and character generator means operative in response to member of said control signals and to data from said memory to provide data representing said second form of information to said imprinting means for printing said second form of information as second selected combinations of said like indicia.

21. A system according to claim 20 wherein said character generator means includes:

a read-only memory containing matrix data for each character to be printed;

means for applying a data word to said read-only memory identifying a character to be printed; and means for applying a second data word to said readonly memory identifying the columns of said matrix data for the associated character to be printed;

said read-only memory being operative in response to said first and second data words to provide output signals to said imprinting means to cause printing of the selected character in the form of a multiple column matrix of indicia. 22. A system according to claim 20 including: means for providing line advance signals to a feed mechanism for said sheet to selectively advance said sheet by a first amount or a second amount in accordance with the form of information being printed. 23. A system according to claim 22 wherein said line advance signal means is also operative to provide a signal to said sheet feed mechanism to retract a sheet to a former line position.

24. In a magnetic printing system which includes means for recording data on a magnetic tape, means for applying toner to the recorded areas of said tape, means for transferring the toner onto a confronting sheet and means for advancing said sheet after transfer of said toner, logic circuitry for providing data to said tape and comprising:

a memory for storing data representing character information and facsimile information to be printed;

means for recognizing said character and facsimile information and for providing respective control signals in response thereto;

means operative in response to the control signal corresponding to said facsimile information to convey data representing said facsimile information from said memory to a recording head of said recording means; and

character generator means operative in response to the control signal corresponding to said character information and to data from said memory representing said character information to provide matrix data to a recording head of said recording means.

25. A system according to claim 24 wherein said logic circuitry includes:

means for providing line advance signals to said sheet advancing means to selectively advance said sheet by a first amount while imprinting character data and a second amount while imprinting facsimile data.

26. A system according to claim 24 wherein said character and facsimile data is received by said printing system from-low level radiation from a video circuit of a television receiver.

27. In a printing system which includes means for printing character and facsimile information in the form of selected combinations of like indicia, logic circuitry for providing data representing said information from a data source and comprising:

means for receiving said data representing character information and facsimile information to be printed; means for recognizing said character and facsimile information and for providing respective control signals in response thereto; means operative in response to the control signal corresponding to said facsimile information to convey data representing said facsimile information to said printing means for printing said facsimile information in the form of first selected combinations of said like indicia; and

character generator means operative in response to the control signal corresponding to said character information to provide matrix data to said printing means for printing said character information in the form of second selected combinations of said like indicia.

28. A system according to claim 27 wherein said character and facsimile data is received by said printing system from low level radiation from a video circuit of a television receiver.

29. A magnetic printing system comprising:

a magnetic recording tape;

tape transport means adapted to move said recording tape in a predetermined path;

magnetic recording means disposed in operative association with said tape for recording data thereon representing information to be printed;

means disposed in operative association with said recording tape for erasing data recorded thereon;

toner means disposed in relation to said tape and operative to apply a magnetic toner to recorded areas on said tape;

a data receiving sheet having a portion thereof disposed in planar confronting relation with a portion of said recording tape;

sheet transporting means for moving said data receiving sheet in a predetermined path;

platen means disposed adjacent a surface of said portion of said tape;

transfer means disposed on the opposite surface of said portion of said tape as said platen means and operative to urge the confronting portions of said tape and said sheet into engagement in a sequential sweep along the length thereof, thereby to transfer said toner on the recorded portions of said tape onto the confronting surface of said sheet;

means for fixing the toner applied to said sheet; and

a wiping sheet interposed between said transfer means and said sheet and operative to minimize spurious forces during urging of said tape and said sheet into engagement.

30. A magnetic printing system comprising:

an elongated magnetic recording tape;

tape transport means adapted to move said recording tape in a predetermined path;

magnetic recording means disposed in operative association with said tape for recording data along the length thereof representing a line of characters to be printed;

means disposed in operative association with said recording tape for erasing data recorded thereon;

toner means disposed in relation to said tape and operative to apply a magnetic toner to recorded areas on said tape;

a data receiving sheet having a portion thereof disposed in planar confronting relation with a portion of said recording tape;

sheet transporting means for moving said data receiving sheet in a predetermined path;

platen means disposed adjacent a surface of said portion of said tape;

transfer means disposed on the opposite surface of said portion of said tape as said platen means and operative to urge the confronting portions of said tape and said sheet into engagement in a sequential sweep along the length of said tape, thereby to transfer said toner on the recorded portions of said tape onto the confronting surface of said sheet for printing of said line of characters;

means for fixing the toner applied to said sheet. 

1. A magnetic printing system comprising: a magnetic recording tape; tape transport means adapted to move said recording tape in a predetermined path; magnetic recording means disposed in operative association with said tape for recoding data thereon representing information to be printed; means disposed in operative association with said recording tape for erasing data recorded thereon; toner means disposed in relation to said tape and operative to apply a magnetic toner to recorded areas on said tape; a data receiving sheet having a portion thereof disposed in planar confronting relation with a portion of said recording tape; sheet transporting means for moving said data receiving sheet in a predetermined path; platen means disposed adjacent a surface of said portion of said tape; transfer means disposed on the opposite surface of said portion of said tape as said platen means and continuously moveable in a repetitive cycle and operative during a portion of each cycle to urge the confronting portions of said tape and said sheet into engagement in a sequential sweep along the length thereof, thereby to transfer said toner on the recorded portions of said tape onto the confronting surface of said sheet; and means for fixing the toner applied to said sheet.
 2. A magnetic printing system according to claim 1 wherein said platen means is formed of a resilient material.
 3. A magnetic printing system according to claim 1 wherein said transfer means includes a resilient member for urging said tape and said sheet into engagement.
 4. A magnetic printing system according to claim 1 wherein said toner means includes means containing a supply of toner; means for applying said toner to said recorded areas of said tape; and means for removing toner from erased areas of said tape while containing said toner substantially within said containing means.
 5. A magnetic printing system comprising: an endless web of magnetic recording tape supported for movement in a closed path; tape transport means for moving said endless web of tape with intermittent motion about said closed path; magnetic recording means including a recording head in operative relation to a surface of said tape for recording data thereon representing information to be printed; a web of sheet material supported for intermittent motion about a predetermined path, said sheet material having a portion disposed in confronting relationship with a portion of said tape having data recorded thereon; sheet transport means for moving said sheet material along said predetermined path; means for applying a magnetic toner to a surface of said tape on areas having recorded data thereon and in a pattern corresponding to the pattern of recorded data; means continuously moveable in a repetitive cycle and operative during a portion of each cycle when said endless web of tapE and said sheet material are at rest to urge the surface of said tape containing said toner into engagement with the confronting surface of said sheet material sequentially along a length of said sheet material, thereby to sequentially transfer said toner onto said sheet material in a pattern defined by said recorded areas; means for fixing said toner applied to said sheet material; and means for erasing said data recorded on said tape after transfer of said toner onto said sheet material.
 6. A magnetic printing system according to claim 5 wherein said transfer means includes: a platen disposed adjacent one surface of said tape; an elongated generally cylindrical transfer cam supported for rotation about its longitudinal axis and disposed with said longitudinal axis along the length of said tape and adjacent the opposite surface of said tape to said platen, said transfer cam including a ridge helically disposed around a predetermined portion of the cylindrical surface thereof and operative to urge the confronting portions of said tape into engagement with the confronting surface of said sheet material to cause sequential transfer of toner from said recorded areas onto said sheet material; and a wiping sheet interposed between said transfer cam and said sheet and operative to minimize spurious forces during wiping of said tape and said sheet into engagement.
 7. A magnetic printing system according to claim 5 wherein said recording means includes a line memory for storing a line of data to be printed; a character generator operative in response to parallel data from said line memory for energization of said multi-track head for recording of data to be printed on said tape; a recording head for recording facsimile data in the form of a sequence of like marks; means for conveying facsimile data to be printed from said line memory to said facsimile head; means for detecting whether data in said line memory is character data or facsimile data and operative to cause transfer of data to said multi-track head or said facsimile head, respectively; and means operative in response to data in said line memory for detecting a line feed signal and to provide control signals to said sheet transport means to govern line spacing of said sheet material.
 8. A magnetic printing system according to claim 5 wherein said tape transport means includes a capstan disposed in driving relationship to said web of magnetic recording tape and adapted for rotation about its axis; said capstan being of cylindrical peripheral configuration for driving said web, except for a peripheral portion disposed away from said web for providing a dwell period for said web during each revolution of said capstan.
 9. A magnetic printing system according to claim 5 wherein said toner means includes a housing having a brush disposed therein and adapted for rotation about its axis; a supply of toner in said housing; an aperture provided in a wall of said housing and disposed adjacent the surface of said tape to which toner is to be applied; said brush upon rotation within said housing being operative to apply toner through said aperture onto said recorded areas of said tape.
 10. A magnetic printing system according to claim 5 wherein said toner means includes means for removing toner from the surface of said tape after data recorded on said tape has been erased.
 11. A magnetic printing system according to claim 10 wherein said toner means includes a cylindrical housing having a cylindrical brush coaxially disposed therein and adapted for rotation about the common axis; a supply of toner in said housing; a first aperture provided in the cylindrical wall of said housing and disposed adjacent the surface of said tape to which toner is to be applied; a second aperture disposed in the cylindrical wall of said housing and disposed adjacent the surface of said tape at a position at which toner is to be removed; said brush upon rotation within said housing being operative to apply toner through said first aperture onto said recorded areas of said tape and to remove through said second aperture toner from the erased areas of said tape, said toner supply remaining substantially within said housing.
 12. A magnetic printing system according to claim 5 wherein said magnetic recording means includes a multi-track recording head for providing a plurality of like data marks on said tape; character forming logic for selectively energizing said multi-track head, said logic including means for storing a character to be printed; counter means for providing digital representations identifying the column of a particular character to be printed; and a read-only memory operative in response to said column identification and said stored character to provide output signals to said multi-track recording head for selective energization thereof.
 13. A magnetic printing system according to claim 12 wherein said signal is applied to said recording head in the form of carrier bursts such that toner is applied to entire recorded areas of said tape.
 14. A magnetic printing system according to claim 5 wherein said transfer means includes: an elongated generally cylindrical transfer cam supported for rotation about its longitudinal axis and including a ridge helically disposed around a predetermined portion of the cylindrical surface thereof and operative to urge the portion of said tape having data recorded thereon into engagement with the confronting surface of said sheet material to cause sequential transfer of toner from said recorded areas onto said sheet material.
 15. A magnetic printing system according to claim 14 wherein said transfer means includes a platen disposed adjacent said tape on a side opposite to said transfer cam.
 16. A magnetic printing system according to claim 14 wherein said ridge is of a resilient material.
 17. A magnetic printing system according to claim 5 wherein said recording head is a multi-track head for providing a plurality of like data marks on said tape, and said recording means includes character forming logic for selectively energizing said multitrack head for applying data onto said tape representing information to be printed.
 18. A magnetic printing system according to claim 17 wherein said recording means further includes memory means for storing one or more lines of data to be printed.
 19. A magnetic printing system according to claim 17 wherein said magnetic recording means includes means for providing crosstalk compensation between adjacent tracks of said multi-track head.
 20. In a printing system which includes means for printing information in the form of selected combinations of like indicia and means for imprinting said indicia on a sheet, logic circuitry for providing said selected combinations of indicia and comprising: a memory for storing data representing first and second forms of information to be printed; means for recognizing each of said forms of information and for providing respective control signals in response thereto; means operative in response to one of said control signals to convey data representing said first form of information from said memory to said imprinting means for printing said first form of information as first selected combinations of said like indicia; and character generator means operative in response to the other of said control signals and to data from said memory to provide data representing said second form of information to said imprinting means for printing said second form of information as second selected combinations of said like indicia.
 21. A system according to claim 20 wherein said character generator means includes: a read-only memory containing matrix data for each character to be printed; means for applying a data word to said read-only memory identifying a character to be printed; and means for applying a Second data word to said read-only memory identifying the columns of said matrix data for the associated character to be printed; said read-only memory being operative in response to said first and second data words to provide output signals to said imprinting means to cause printing of the selected character in the form of a multiple column matrix of indicia.
 22. A system according to claim 20 including: means for providing line advance signals to a feed mechanism for said sheet to selectively advance said sheet by a first amount or a second amount in accordance with the form of information being printed.
 23. A system according to claim 22 wherein said line advance signal means is also operative to provide a signal to said sheet feed mechanism to retract a sheet to a former line position.
 24. In a magnetic printing system which includes means for recording data on a magnetic tape, means for applying toner to the recorded areas of said tape, means for transferring the toner onto a confronting sheet and means for advancing said sheet after transfer of said toner, logic circuitry for providing data to said tape and comprising: a memory for storing data representing character information and facsimile information to be printed; means for recognizing said character and facsimile information and for providing respective control signals in response thereto; means operative in response to the control signal corresponding to said facsimile information to convey data representing said facsimile information from said memory to a recording head of said recording means; and character generator means operative in response to the control signal corresponding to said character information and to data from said memory representing said character information to provide matrix data to a recording head of said recording means.
 25. A system according to claim 24 wherein said logic circuitry includes: means for providing line advance signals to said sheet advancing means to selectively advance said sheet by a first amount while imprinting character data and a second amount while imprinting facsimile data.
 26. A system according to claim 24 wherein said character and facsimile data is received by said printing system from low level radiation from a video circuit of a television receiver.
 27. In a printing system which includes means for printing character and facsimile information in the form of selected combinations of like indicia, logic circuitry for providing data representing said information from a data source and comprising: means for receiving said data representing character information and facsimile information to be printed; means for recognizing said character and facsimile information and for providing respective control signals in response thereto; means operative in response to the control signal corresponding to said facsimile information to convey data representing said facsimile information to said printing means for printing said facsimile information in the form of first selected combinations of said like indicia; and character generator means operative in response to the control signal corresponding to said character information to provide matrix data to said printing means for printing said character information in the form of second selected combinations of said like indicia.
 28. A system according to claim 27 wherein said character and facsimile data is received by said printing system from low level radiation from a video circuit of a television receiver.
 29. A magnetic printing system comprising: a magnetic recording tape; tape transport means adapted to move said recording tape in a predetermined path; magnetic recording means disposed in operative association with said tape for recording data thereon representing information to be printed; means disposed in operative association with said recording tape for erasing data recorded thereon; toner means disposed in relatIon to said tape and operative to apply a magnetic toner to recorded areas on said tape; a data receiving sheet having a portion thereof disposed in planar confronting relation with a portion of said recording tape; sheet transporting means for moving said data receiving sheet in a predetermined path; platen means disposed adjacent a surface of said portion of said tape; transfer means disposed on the opposite surface of said portion of said tape as said platen means and operative to urge the confronting portions of said tape and said sheet into engagement in a sequential sweep along the length thereof, thereby to transfer said toner on the recorded portions of said tape onto the confronting surface of said sheet; means for fixing the toner applied to said sheet; and a wiping sheet interposed between said transfer means and said sheet and operative to minimize spurious forces during urging of said tape and said sheet into engagement.
 30. A magnetic printing system comprising: an elongated magnetic recording tape; tape transport means adapted to move said recording tape in a predetermined path; magnetic recording means disposed in operative association with said tape for recording data along the length thereof representing a line of characters to be printed; means disposed in operative association with said recording tape for erasing data recorded thereon; toner means disposed in relation to said tape and operative to apply a magnetic toner to recorded areas on said tape; a data receiving sheet having a portion thereof disposed in planar confronting relation with a portion of said recording tape; sheet transporting means for moving said data receiving sheet in a predetermined path; platen means disposed adjacent a surface of said portion of said tape; transfer means disposed on the opposite surface of said portion of said tape as said platen means and operative to urge the confronting portions of said tape and said sheet into engagement in a sequential sweep along the length of said tape, thereby to transfer said toner on the recorded portions of said tape onto the confronting surface of said sheet for printing of said line of characters; means for fixing the toner applied to said sheet. 